Roadway luminaire and methods of use

ABSTRACT

A lighting apparatus having a base member and a directional member are shown and described. The base member includes a first surface having a plurality of reflective elements extending therefrom. The base member also including a plurality of openings arranged in a pattern. Each opening is configured to receive a respective light source. The directional member has a portion of a reflective surface positioned relative to at least one opening to reflect light radiating from a lighting source disposed within the opening towards a portion of at least one of the reflective elements extending from the base member.

This application is a continuation application of U.S. patentapplication Ser. No. 13/800,955 filed Mar. 13, 2013, now allowed, whichis a continuation application of U.S. patent application Ser. No.13/429,863 filed Mar. 26, 2012, now issued as U.S. Pat. No. 8,434,893,which is a continuation application of U.S. patent application Ser. No.13/150,625 filed Jun. 1, 2011 and now issued as U.S. Pat. No. 8,177,386,which is a continuation application of U.S. patent application Ser. No.12/754,090 filed Apr. 5, 2010 and now issued as U.S. Pat. No. 8,002,428,which is a continuation application of U.S. patent application Ser. No.12/166,536 filed Jul. 2, 2008 and now issued as U.S. Pat. No. 7,828,456,which claims priority to U.S. Provisional Patent Application Ser. No.60/980,562 filed Oct. 17, 2007.

FIELD OF THE INVENTION

The present disclosure relates generally to a luminaire and, moreparticularly, to a luminaire for lighting a roadway or the like and,even more particularly, to a luminaire directing light from its one ormore light sources in more than one direction. The disclosure findsparticularly useful application when the luminaire employs multiplelight sources including, in one embodiment, one or more light emittingdiodes (LEDs).

BACKGROUND OF THE INVENTION

Highway and roadway lighting have used incandescent and more recentlyhigh intensity discharge (HID) luminaire s that can provide adequateamounts of lighting, but which have several drawbacks, includingfrequent (at least annually) luminaire failures and uneven lighting ofthe traffic surface. Such lighting also disperses the light in alldirections around the luminaire. Uncontrolled light can be wasted inlighting areas around the roadway that do not require lighting, andcontributes to unwanted “night lighting” which can interfere with thepreservation and protection of the nighttime environment and ourheritage of dark skies at night.

As advances in the quality and energy efficiency of lighting sourcessuch as LEDs have improved, their production costs have gone down. As aresult, LEDs, for example are being commonly used in area lightingapplications. Initial efforts to incorporating LEDs into lightingfixtures have involved retrofitting LEDs into conventional luminaries oronto or into the shape of conventional lighting luminaire s.

Improvements in LED lighting technology has led to the development byOsram Sylvania of an LED having an integral optic that emits asignificant portion of the LED light bilaterally and at high angle α(about 60°) from nadir, which is available as the Golden DRAGON® LEDwith Lens (hereinafter, “bilateral, high angular LED”). FIG. 1A is arepresentation of the bilateral, high angular LED 252 showing thedirection and angle of the lines 255 of maximum light intensity emittedby the LED, substantially in opposed designated ±Z axes. Progressivelyand significantly lower levels of light intensity are emitted at anglesin the Y-Z plane diverging from lines 255 and along vectors directedtoward the transverse direction (±X axes) normal to the image of thefigure. The radiation characteristics of the LED 252 are shown in FIG.1B.

These LEDs can be used in a matrix arrangement in a lighting apparatusto distribute more of the light emitted from the LEDs, for example,along the length of the roadway and down both sides of the light pole.In a typical matrix, the LEDs are arranged in eighteen longitudinalrows, with five bilateral, high angular LEDs in each row. The ninetytotal bilateral, high angular LEDs are arranged with 36 bilateral, highangular LEDs (42%) aligned with its Z axes aligned within the housingalong the longitudinal direction L, to align with the direction of theroadway; 27 bilateral, high angular LEDs (29%) aligned with its Z axesaligned +10° (toward the roadway) from the longitudinal direction L inthe direction of traffic; and 27 bilateral, high angular LEDs (29%)aligned with its Z axes aligned −10° (away from the roadway) from thelongitudinal direction L in the direction of traffic.

The LED lighting apparatus can be retrofitted onto existing light poles,or installed onto new light poles, for illuminating the lanes of alltypes of roadways, including two-way streets up to multi-lane interstatehighways. As shown in FIG. 2A, the light poles are typically mounted onthe sides of such roadways, typically several meters into the berm fromthe edge 5 of the roadway so as not to become an obstruction to traffic.Arm 4 extending from the pole 3 is configured to hold the luminaireoutward toward the roadway 7. Because a large portion of the lightemitted by the bilateral, high angular LEDs is directed longitudinallyand in the directions (±L) that the roadway 7 runs, and since theroadway luminaire is typically mounted near the berm of the roadway 7 oronly partly into the first or near lane 7 n, adjustments to theluminaire must be made to ensure that emitted light is projected outinto outer lanes (for example, to outer lane 70 of the roadway. It isknown to accomplish the projection of the emitted light by tilting theluminaire on an angle β from nadir to angle and disperse a significantportion of the light to the outer lane 7 f or outer lanes of the roadway7. Such angle β is typically between about 20° to about 70°, and moretypically about 30°. FIG. 2B shows a simulated light distributionpattern formed by at least two conventional LED lighting apparati 18 aand 18 b secured to the arm of the lighting pole, positioned 30 feet(9.1 m) above the roadway and extending over the roadway four feet (1.2m) in from the near edge 5 of the roadway, and positioned 70 feet (21 m)apart. The rectangular light distribution pattern 80 is defined by thetraverse centerlines of the apparati 18 a and 18 b, the near edge 5, anda simulated outer edge 9 extending parallel to and 20 feet (6.1 m)laterally from the near edge 5. Each LED lighting apparati has 90 LEDsarranged in an array of 18×5 LEDs, consisting of 18 LEDs on a substrateat 1 inch (2.54 cm) spacing, with the five parallel substrates orientedin the traverse T direction, and spaced apart by about 1 inch in thelongitudinal L direction. Each LED is the bilateral, high angular LED252, as shown in FIG. 1, and is powered with 1 watt and emits 48 lumens.

While providing a significant improvement in the distribution of lightalong the length of the roadway, the tilting of the luminaire at highangles β from nadir also directs light toward the horizon (H),contributing to unwanted “night lighting” and creating the potential fordirect light glare in the eyes of drivers and passengers in automobilesand trucks, particular those in outer lane 7 f or lanes farthest fromthe near edge 5, including those traveling in roadway lanes with trafficmoving in the opposite direction. The light directed into the horizon iswasted light resulting in wasted energy costs to power the LEDs. Tiltingthe luminaire is thus an inefficient manner of obtaining a proper lightdistribution.

SUMMARY OF THE INVENTION

The present disclosure relates to a lighting apparatus configured toefficiently distribute light, and in particular, efficiently distributelight for illuminating roadway surfaces and, more particularly theillumination of roadway surfaces with one or more lighting sources suchas LEDs in an exemplary embodiment.

In one embodiment, the present disclosure relates to a lightingapparatus having: a housing comprising a planar base; a plurality oflight sources forming a matrix having a plurality of rows oriented in adesignated opposed longitudinal directions L, and a plurality of columnsoriented in an opposed direction T transverse to the direction L; and aplurality of elongated reflectors having a reflective surface, eachreflector having an elongated proximal edge disposed adjacent to atleast one of the plurality of rows, and a distal edge, wherein thereflective surface faces the at least one row, and each reflectivesurface being oriented in a plane generally normal to the planar base,for reflecting a portion of the light from the at least one row of lightsources emitted in a −T direction, toward the +T direction.

The present disclosure also relates to the lighting apparatus abovewherein the light sources are LEDs and, more particularly wide-angleLEDs, each wide-angle LED having a light-refracting optic lens thatdistributes a significant portion of the LED light in ±Z direction andat an angle α from nadir of at least about 50°, and wherein plurality ofwide-angle LEDs are oriented on the planar base with the ±Z directionoriented substantially along the ±L direction.

The present disclosure further relates to a roadway lighting assemblyfor lighting a roadway, comprising: a lighting apparatus according toany one of the above lighting apparati; and a housing for associatingthe lighting apparatus with a conventional street light pole, whereinthe planar base of the lighting apparatus is positioned substantiallyparallel to the plane of the surface of the roadway.

In another aspect, a lighting apparatus is shown and described. In oneembodiment, the apparatus includes a base member and a directionalmember. The base member includes a first surface having a plurality ofreflective elements extending therefrom. The base member also includes aplurality of openings arranged in a pattern such that each opening beingconfigured to receive a respective light source. The directional memberhas a portion of a reflective surface positioned relative to at leastone opening to reflect light radiating from a lighting source disposedwithin the opening towards a portion of at least one of the reflectiveelements extending from the base member.

In various embodiment, the first surface of the base member can bereflective. Also, the base member and the reflective elements can beformed integrally with one another. The cross-section of a portion ofthe reflective member can be substantially v-shaped. The lightingapparatus can also include a pair of side members.

In another aspect, the disclosure is directed to a luminaire. Theluminaire, in one embodiment, includes a housing, a plurality oflighting sources, a base member, and a plurality of directional members.The plurality of lighting sources can be arranged in a substantiallymatrix-like pattern.

The base member is disposed within the housing and includes a firstsurface having a plurality of integrally formed reflective elementsextending therefrom. The base member also includes a plurality ofopenings arranged in a complementary matrix-like pattern. Each openingreceives a respective light source.

The plurality of directional members are spaced apart from one anotherand extend substantially perpendicular to the plurality of reflectiveelements. Each of the directional members passes through a portion of arespective set of reflective elements such that a portion of areflective surface of the directional members is positioned to reflectlight radiating from a lighting source in a respective opening.

The disclosure additionally relates to the ornamental shape and designof the lighting apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows a prior art wide-angle LED with refractor of the typefinding use in the present disclosure.

FIG. 1B shows the radiation characteristics of the wide-angle LED ofFIG. 1A.

FIG. 2A shows an elevation view of a conventional roadway lightingapparatus using the wide-angle LED of FIG. 1A, with the luminaire tiltedat an angle β upwardly in a direction transverse to the direction of theroadway.

FIG. 2B shows a plan view of a simulated light distribution patternformed by two adjacent conventional roadway lighting apparatus on aroadway as shown in FIG. 2A.

FIG. 3 shows an elevation view of one embodiment of a lighting apparatusof the present disclosure positioned on a light pole along a roadway.

FIG. 4 shows a perspective view of the lighting apparatus as viewed fromline 4-4 of FIG. 3.

FIG. 4A shows a detailed view of a portion of the FIG. 4 apparatus,illustrating the positioning and orientation of a light source.

FIG. 5 shows an exploded view of the lighting apparatus of FIG. 4 in anembodiment employing LEDs as light sources.

FIG. 6 shows a cross sectional view of the lighting apparatus of FIG. 4as viewed from line 6-6.

FIG. 7A shows a plan view of a simulated light distribution patternformed by an embodiment of the lighting apparatus as illustrated in FIG.3, employing LEDs as light sources and with a reflector angle δ of −10°.

FIG. 7B shows a plan view of a simulated light distribution patternformed by an embodiment of the lighting apparatus as illustrated in FIG.3, employing LEDs as light sources and with a reflector angle δ of −15°.

FIG. 8 shows a cross sectional view of an embodiment of the reflectorformed from the cover plate.

FIG. 9 shows a cross sectional view of another embodiment of thereflector formed from the cover plate.

FIG. 10 shows an isometric view of another embodiment of the reflector.

FIG. 11A shows a top view of a portion of the reflector of FIG. 10.

FIG. 11B shows a side view of the of a portion of the reflector of FIG.10.

FIG. 11C is an end view of a portion of the reflector of FIG. 10 withouta directional member.

FIG. 11D is a blown-up isometric view of a portion of the reflector ofFIG. 10.

FIG. 12A is a side view of a portion of the reflector of FIG. 10 showwithout a directional member.

FIG. 12B is a top view of a portion of the base member prior to bending.

FIG. 13 is a top view of an embodiment of a side member of the reflectorof FIG. 10.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 3 shows an embodiment of the lighting apparatus 10 of the presentdisclosure comprising a roadway light pole assembly 1 that includes apole 3, an arm 4 and pole adapter 6. The pole 3 is positioned away fromthe near edge 5 of the roadway 7, having a near lane 7 n and a far lane7 f. FIG. 5 shows an exploded view of the lighting apparatus of FIG. 4.FIG. 6 shows a transverse sectional view of the apparatus of FIG. 4,including a housing 20 having a rectangular planar base 21 and aplurality of light source assemblies 50. In the depicted embodiment, thelight sources are comprised of LEDs. The lighting apparatus 10 of thepresent disclosure can, however, employ any type of light source knownto date or hereinafter created. Although, the remainder of thespecification describes various embodiments of the disclosure employingLEDs as the light sources, the LEDs can be replaced with any lightsource known to date or hereinafter created. In the embodiment depictedin FIG. 4, the light sources comprise LED assemblies 50 a and 50 b (asdepicted in FIG. 5), affixed to an underside surface of the planar base21. The planar base 21 has an opposed upper surface that attaches,directly or indirectly, to the pole adaptor 6 for securing the housing20 to the extending arm 4 of a roadway or parking lot light pole 3.Existing extending arms 4 are typically positioned horizontal to theroadway 7, although some existing arms can be upwardly tilted slightly,generally less than about 5° from true horizontal to the roadway 7.Other housing shapes can be made in accordance with the presentdisclosure, including round, square, oval and other irregular shapes.

The housing 20 of the lighting apparatus embodiment depicted in FIG. 4includes sidewalls, illustrated as pairs of opposed perimeter sidewalls25 and 26, disposed around the perimeter of the planar base 21. Thesidewalls 25, 26 are configured to extend from an outer edge of theplanar base 21, to a distal edge 28, and may be formed integrally withthe planar base of the housing. The protruding sidewalls 25, 26 define acavity 48 within which the LED assemblies 50 are mounted. In theembodiment depicted in FIG. 5, the housing base 21 comprises recesses toaccommodate the lighting assemblies 50. In the embodiment of FIG. 5, thelight assemblies 50 are each comprised of elongated substrate 51 onwhich multiple LEDs 52 reside. The scope of the present disclosurecontemplates any size and shape of substrates each with any number ofLEDs (or other light source) thereon such that each LED could be on adedicated substrate or every LED of the lighting assembly could beincluded on a single substrate of whatever shape and size necessary ordesired. In the illustrated embodiment, the sidewalls are curved andextend downward. As depicted in FIG. 5, the base 21 may compriserecesses 24 to accommodate the size and shape of the light assemblies50. The light assemblies could, however, be placed on the base 21without the use of recesses 24. Other sidewall configurations can beplanar and rectilinear. The sidewalls may be joined at their adjacentbeveled ends to form a substantially enclosed wall around the perimeterof the planar base 21 of the housing to define the cavity 48. In oneembodiment, a planar ledge or rim 29 extends inwardly from proximate thedistal edges 28 along the lengths of the sidewalls to define an opening27, to provide a means for positioning and affixing, proximate thereto,the perimeter edge of a lens 60, for covering the opening 27 to thecavity 48 in the housing 20.

In an aspect of the disclosure, the lighting assembly 10 can alsoinclude a cover plate 62 comprising abuse 63 having a plurality ofopenings 66 defined by opening edges 67. The cover plate 62 ispositioned in the cavity 48 of the housing, over the LED assemblies 50,with the openings 66 registered around the LEDs 52 as shown in FIG. 6.The cover plate 62 is typically secured to the housing 20 by knownmeans, including threaded bolts and nuts, screws, clips, latches, andrivets. The side portions 64 and end portions 65 of the cover plate 62generally extend outward from the base 63, and are tapered outwardlytoward the distal edge 28 of the housing 20, or beyond the rim 27,within the cavity 48, or short of the rim 27 as shown in FIG. 6. Thecover plate 62 can be made from a reflective material or have areflective coating or be highly finished to provide a reflective surfacefinish, or other decorative pattern. The cover plate 62 also serves todisguise the electronic circuitry and, when the light sources are LEDs,the substrates 51 of the light source assemblies 50 and improve theappearance. The openings 66 can be of any shape, such as circular oroval, preferably matching the shape of the associated light sourceemployed, though other opening shapes can be used. The cover plate 62can be secured in place to the housing by any of the various knownconventional means, such as with rivets, screws, bolts, clips, latches,and adhesives. In certain embodiments, the cover plate 62 can be adheredor attached to the inside surface of the planar base 21, advantageouslywhen the LED assemblies are dispose within recesses 24 formed in theplanar base 21, as described below.

The depicted light source assemblies 50 comprise a substrate 51 on whichis mounted a plurality of LEDs 52, in a row. An LED may be a unitconsisting of the light-generating diode and an associated optic or thelight-generating diode without the optic. When present, the associatedoptic can be affixed directly to the diode, can be affixed to thesubstrate in a position next to or in contact with the diode by separatepositioning and orientation means, or located or held without theassistance of the substrate or diode. The LED can be of any kind andcapacity, though in a preferred embodiment, the plurality of LEDs eachprovide wide-angle light distribution pattern oriented primarily indesignated ±Z axes. A typical LED used in the present disclosure is thewide-angle LED known herein as the bilateral, high angular LED 252, suchas Golden DRAGON® LED manufactured by Osram Sylvania. The LED assemblies50 are shown disposed in position within the housing 20 along atransverse axes “T” of the LED lighting apparatus 10, though they canalso be positioned along or at an angle to the longitudinal axes ±L. Thenumber of LEDs on a substrate, can vary according to the lighting need,and typically range from about 5 to about 20 LEDs, or more. An increasednumber of LEDs may be employed on a substrate to provide the amount oflighting necessary for a wider roadway, or more generally, for atransversely wider lighting pattern. The number of substrates likewisecan vary with the lighting need, and may include about 4 to about 10substrates. The spacing between these adjacent LED lighting assembliesmay be dependent upon the angle α of the bilateral, high angular LED.

The lighting apparatus of the present disclosure can also include anintermediate heat transfer means which may be accomplished by coverplate 62 (not depicted), such as a sheet of aluminum, that can bedisposed over and in heat-transferring contact with the top surface ofthe substrate, which when using LEDs is typically a printed circuitboard (PCB), to extract and conduct heat away from the light sources.Like the cover plate 62, the intermediate heat transfer means hasopenings that register over the light sources to allow emission oflight. The openings are formed proximate to the light sources, which isthe source of the heat generated, to optimize heat extraction.

In the embodiment shown in FIG. 4A, the Z axis of each of the wide-angleLEDs 52 in the matrix is disposed an angle θ from the row of LEDs alongline 200, which in the illustrated embodiment is shown parallel tolongitudinal direction L, where the angle θ typically ranges withinabout ±15°, more typically within about ±10°. The angle θ of one or moreof the LEDs is typically varied proportionally with the requiredtransverse projection of light from the luminaire. Thus, for a widerroadway requiring a wider transverse projection of light from theluminaire, the absolute value of the angle θ is increased. The typicaldistribution and layout of the plurality and matrix of LEDs provides adistribution of the angle θ among the matrix of LEDs, wherein about15-35% of the LEDs have an angle θ equal to about +5° to +15°; about15-35% of the LEDs have an angle θ equal to about −5° to −15°; and about30-70% of the LEDs have an angle θ equal to about −5° to +5°.

At least one reflector 70 is disposed generally in the longitudinaldirection L of the lighting apparatus 10. The one or more reflectorsredirect light as needed or desired. Employing multiple reflectors 70can facilitate redirecting light emanating from different light sourcesin different directions. This permits creation of zones of lightintensity in desired locations, such as a near and far lane of aroadway. By directing the light using reflectors 70, inefficiencies canbe avoided such as with the tilting of light apparatus 18 at angle.beta. in FIG. 2 a. Each of the one or more reflectors 70 comprises anelongated, rectangular reflective surface, usually but not necessarilyplanar, that faces an adjacent line of light source, and having alongitudinal proximal (or directionally upper) edge 73 (see FIG. 6) thatis positioned next to, and typically directly adjacent, a row 200 oflight sources. Although depicted as redirecting from LEDs, thereflectors 70 of the instant disclosure can be employed to redirectlight from any light source. Positioning the proximal edge 73 of thereflector vertically adjacent the LED allows the reflector to redirectlight. Each reflector 70 typically has first and second side ends 72,and a distal (or directionally lower) edge 71 that extends away from theLED. A reflector 70 can be associated with some or all of the pluralityof rows of LEDs. The reflector 70 can be disposed proximate severalconsecutive rows of the LEDs, including those rows at the −T end ofhousing.

The reflector 70 is typically a planar sheet that is sufficiently rigidto maintain its shape. A typical planar sheet material is about 5-250mil (about 0.1-6 mm) thick. The reflective surface is typically afinished surface having a reflectance of at least 86%, more typically ofat least 95%. An exemplary reflector is a sheet of aluminum having aMIRO 4 finish, manufactured by Alanod GMBH of Ennepetal, Germany, on atleast one side that faces the adjacent row of LEDs. The reflectors canbe of any size, shape or orientation in order to redirect light asdesired. Two of the contemplated reflector configurations are depictedin FIGS. 8 and 9 as being integral with cover plate 62, therebylessening the total number of discrete elements in the lightingapparatus.

Conventional hardware secures or fixes the reflectors 70 in position tothe housing 20. In this embodiment, the one or more reflectors 70 can bepositioned on the reflective surface and secured to the sides 64 of thecover plate 62. The sides 64 are oriented generally in the transversedirection ±T and disposed at the opposed sides of the inner cavity 48 ofthe housing 20. Each side 64 has slots 76 formed in the inwardly facingsides that position and aid in retaining the longitudinal ends 72 of thereflectors 70. The slots define the planar angle of the reflectors. Theslots can be arranged at the same angles, and at equal distances alongthe side 64, or at different angles or distances.

The one or more reflectors 70 can also be formed integrally with thesheet material of the reflective surface of the cover plate 62, byfolding the cover plate material along the proximal edge and at thedistal edge, and folding again at the proximal edge to form a series ofreflector 70. FIG. 8 and FIG. 9 show two configurations of the coverplate 62 folded to provide the reflectors 70. When integrally formedwith the cover plate 62, the reflectors 70 assist in dissipating heatfrom the light sources.

The elongated reflector 70 is typically planar, with its plane 300oriented at an angle δ from a line N′ normal to the planar base 21 ofthe housing, as shown in FIGS. 6 and 8. In one embodiment, the presentdisclosure is configured for a conventional roadway or parking lightpole where the line N′ lies substantially along true vertical. The angleδ of the reflector 70 provides improved distribution and control oflight without unwanted direct glare and “night lighting”, and providesadjustability when the base of the housing 20 is slightly angled fromthe true horizontal plane such as when retrofitting a pre-existing lightpole. The angle δ is typically within the broad range of about 0° toabout −20°, wherein a negative angle δ is where lower edge 71 tilts awayfrom the adjacent light source in the −T direction. Any angle δ is,however, contemplated to provide the desired light distribution for agiven installation. In one preferred embodiment, the planar base 21 ofthe lighting apparatus is disposed normal to true vertical or nadir N,and the angle δ is more typically within the following ranges: about −2°to about −18°, about −5° to about −18°, about −5° to about −15°, about−7° to about −15°, about −7° to about −12°, and about −10° to about−15°. Where the planar base 21 is tilted upward on a slight angle β fromtrue vertical, toward the +T direction, the angle δ can be disposed at aslightly more negative angle, relative to normal line N′. Where theroadway surface is not normal to true vertical, the planar base 21 mayoptimally be oriented parallel to the roadway surface

Referring to FIG. 6, the spacing and distance of the planar reflector 70from the light sources, and the height (h) of the reflector 70, areselected to guide the emitted light toward the roadway (in the +Tdirection), and to minimize obstructing emitted and reflected light fromone reflector 70 c that might strike the back surface of an adjacentreflector 70 d. The reflector is preferably positioned with its upperedge 73 adjacent to the light sources in the row. The height “h” of thereflector may be about the same as the spacing distance, designated “s”,between adjacent rows of light sources. The ratio h:s is preferablyabout 0.5-2:1, and more preferably about 0.5-1.2:1.

In another embodiment, the reflectors 70 can be secured directly to thehousing, or indirectly via a separate bracket or other known means thatis affixed to the housing 20 when a cover plate is not inserted into thecavity 48. The reflectors can be affixed within slots, or other knownsecurement means, such as with rivets, screws, bolts, clips, latches,and adhesives.

The associated electronic and electrical components for powering andcontrolling the luminaire may be disposed within the pole adapter 6, andreceive electrical power wiring and optional control wiring via the arm4 of the pole. The circuitry for controlling and powering the lightsources 52 is known to those of ordinary skill in the art and can bemounted in part or in whole on a PCB, or located remotely. The lightingapparatus 1 typically receives an external power supply having anoff-line voltage of 110-277 V, depending upon the local power system. Inone embodiment, an external low voltage power system can be providedthat converts the off-line voltage of 110-277 V AC from the local powersystem to the 24V constant current required for the light source powerand control components of the light source assembly. In anotherembodiment, the lighting apparatus is configured for installation of anintegrated power and control module, which converts off-line powerdirectly to the low voltage constant current power, which may berequired by the light source. The drivers and controllers of LED boards,when employed, are routinely powered with 24V constant current, whichcan be mounted within the housing 20.

The housing may be constructed of aluminum by well-known methods such asformed sheet metal, die casting, permanent mold casting, machining orsand casting. Other parts, such as the cover plate, can also be made ofaluminum. The housing and other parts can also be made of other metalssuch as bronze and brass. The parts can also be made of engineeringplastic materials, such as by injection molding.

A typical method of forming the sheet metal aluminum housing employs abrake press that secures the base portion in a plane, and folds thesides to the desired angle relative to the base. The folded sides arethen confined in position while welding together the ends of thesidewalls, which maintains the planar shape of the base. The lightsource assembly, cover plate, power frame and other components can beassembled to the housing a variety of known fastening or fixing means,including screws, bolts, rivets, welds, ties, latches, adhesives, andother known means. Threaded pins can be threaded or secured into tappedholes in the underside of the housing, and can be extend through holesformed in the cover plate and power frame, and optionally through thelight source assembly board, and can be capped with a nut to secure theelements to the housing.

In an alternative embodiment of the luminaire, the light source assemblycan be disposed within the recess 24, discussed above, formed in theplanar base of the housing, as shown in FIG. 5 and as described inco-pending U.S. provisional patent application 60/953,009, filed Jul.31, 2007, the disclosure of which is incorporated herein by reference.The recess is typically formed into the planar material of the planarbase, such as by stamping or forming. The floor of each recess can liein the same plane as the planar base, or in a plane offset from theplanar base, typically in a direction opposite the LED attachmentsurface. The recesses are typically substantially linear, with roundedends, though other recess and end shapes can be used, as needed, such asround, square, oval, and other irregular shapes.

Each recess has a wall that defines the perimeter of the recess.Typically, the wall is continuous around the perimeter of the floor,though in some embodiments, there can be a break in the wall. The heightof the wall typically defines the depth of the recess, for purposes ofpositioning and securing the light source assembly, as discussed hereinafter.

The light source assembly can be assembled into the recess, typically byplacing the light source assembly into heat-transfer contact with thefloor of the recess. Optionally, a small amount of epoxy resin, prior tosetting, can be applied to the floor of the recess to act as an adhesiveto attach the light source assembly to the housing. The epoxy resin maythen be poured over the light source assembly and into and around thevoid of the recess. The epoxy resin can completely bury or encase thesubstrate of the light source assembly, although portions of thesubstrate and the void can be filling or covered with the epoxy. Theepoxy resin can then be cured, by means well known in the art, includingthe passing of time, heat, UV light, and others.

The potting epoxy secures the light source assembly within the recess,and isolates the light source and circuitry from water, dust, dirt andother elements of the environment. The recesses also assist in theassembly of the lighting assemblies, particularly when manufacturing thesame by hand, by defining the location of the light source assemblyexactly.

When employing LEDs, the substrate 51 is typically a light board, andmore typically a PCB. The circuitry for controlling and powering theLEDs can also be mounted on the PCB, or remotely. In one suitableembodiment, the LEDs 52 are white LEDs each comprising a gallium nitride(GaN)-based light emitting semiconductor device coupled to a coatingcontaining one or more phosphors. The GaN-based semiconductor deviceemits light in the blue and/or ultraviolet range, and excites thephosphor coating to produce longer wavelength light. The combined lightoutput approximates a white output. For example, a GaN-basedsemiconductor device generating blue light can be combined with a yellowphosphor to produce white light. Alternatively, a GaN-basedsemiconductor device generating ultraviolet light can be combined withred, green, and blue phosphors in a ratio and arrangement that produceswhite light. In yet another suitable embodiment, colored LEDs are used,such are phosphide-based semiconductor devices emitting red or greenlight, in which case the LED assembly 50 produces light of thecorresponding color. In still yet another suitable embodiment, ifdesired, the LED light board includes red, green, and blue LEDsdistributed on the PCB in a selected pattern to produce light of aselected color using a red-green-blue (RGB) color compositionarrangement. In this latter exemplary embodiment, the LED light boardcan be configured to emit a selectable color by selective operation ofthe red, green, and blue LEDs at selected optical intensities.

In one embodiment, the substrate 51 comprises PCB such as FR4 board, anda metal core sheet or strip that is laminated to the FR4 board withthermally-conductive adhesive or epoxy. The metal core strip istypically bonded to the planar base, such as the floor of a recess, witha thermally-conductive adhesive to secure the substrate 51 to the planarbase. FR4, an abbreviation for Flame Resistant 4, is a composite of aresin epoxy reinforced with woven fiberglass mat. The metal core aids inheat dissipation from the LED. The LED itself typically has aspecialized slug integrated with the LED casing to conduct heat producedby the interior die away from the LED, as is well known in the art. TheFR4 board typically has a top layer of copper that can include a networkof flattened copper connectors or traces for making electricalconnections between components and for conducting heat away from theLED.

In an alternative embodiment, the substrate comprises a non-metallic,non-conductive board, typically an FR4 board, but does not include ametal core layer, which is affixed or attached directly to the planarbase to provide the heat dissipation function of the metal core. Athermally-conductive adhesive or epoxy as a bead or layer of adhesivebonds the board to the base. Use of the FR4 board without metal corereduces the cost of the LED assembly by eliminating the metal core,whose function of transferring heat is assumed by the planar base. Inaddition, elimination of the metal core opens an opportunity to provideflexible or bendable substrates that can be installed into and orattached onto non-planar, curved surfaces. The substrate can comprise apair of FR4 boards separated by a second copper or conductive layer.Each of the pair of FR4 boards is typically thinner to minimizeresistance to heat transfer, while the second copper or conductive layerenhances heat transfer away from the LED. One of either, or both of, thefirst copper layer or the second copper layer is the network of copperconnectors or traces, while the other is primarily a heat transfer aid.

The present disclosure provides several advantages over other methodsand devices for lighting roadways using LEDs that provide a wide-angle,bilateral light distribution pattern. The LED housing can be positionedsubstantially horizontally, normal to nadir, which simplifiesretrofitting of the luminaire onto existing light poles. Second,horizontal glare is significantly reduced or eliminated, as compared tothe conventional installation of conventional and wide-angle LEDs asshown in FIG. 2A. The adjustability of the angle δ of the reflector 70also allows the installer to fine tune the reflector installation,regardless of the angle and orientation of the extending arm of thelight pole 3. Also, orienting of individual LEDs at an angle ±θ resultsin directing more light in the +T direction, away from the roadway. Theuse of reflectors in the present disclosure, disposed inboard andadjacent several of the plurality of rows of LEDs, reflects much of thelight directed in the −T direction outwardly in the +T direction.

FIGS. 7A and 7B show simulated light distribution patterns formed by atleast two LED lighting apparati 10 a and 10 b of the present disclosureon a roadway, substantially as illustrated in FIG. 3. Each LED lightingapparatus 10 a and 10 b is secured to the arm of the lighting pole,positioned 30 feet (9.1 m) above the roadway and extending over theroadway four feet (1.2 m) in from the near edge 5 of the roadway. Theadjacent two LED lighting apparati 10 a and 10 b are positioned 70 feet(21 m) apart, and define there between a rectangular light distributionpattern 80 bounded by the traverse centerlines of the apparati 10 a and10 b, the near edge 5 and a simulated outer edge 9 extending parallel toand 20 feet (6.1 m) from the near edge 5. Each LED lighting apparati has90 LEDs arranged in an may of 18×5 LEDs, consisting of 18 LEDs on asubstrate at 1 inch (2.54 cm) spacing, with the five parallel substratesoriented in the traverse T direction, and spaced apart by about 1 inchin the longitudinal L direction. Each LED is a bilateral, high angularLED, as shown in FIG. 1, that is powered with 1 watt and emits 48lumens.

Each of the first 12 rows of LEDs, starting from the −T end of theapparatus, have positioned adjacent thereto a linear reflector of height0.75 inches (1.9 cm), oriented at an angle δ. The remaining 6 rows ofLEDs have no reflector. An apparatus with an angle δ equal to −10° isshown in FIG. 7A, while an apparatus with an angle δ equal to −15° isshown in FIG. 7B. The light distribution pattern in FIG. 7A has slightlymore light distributed to the simulated outer edge 9, while the lightdistribution pattern in FIG. 7B has slightly more light distributed tothe simulated inner edge 5. The light distribution patterns generated bythe LED lighting apparatus of the present disclosure is at leastcomparable to the light distribution pattern shown in FIG. 2B of theconventional roadway lighting apparatus shown in FIG. 2A. It can be seenthat the LED lighting apparatus of the present disclosure directs lesslight in the −T direction, away from the near edge 5 of the roadway, ascompared to other roadway lighting apparatus.

While the desired light distribution is accomplished in the priorexample by the use of reflectors with some rows of light sources but notothers, it is contemplated that any desired lighting distribution couldalso be accomplished by using reflectors with all rows of light sourcesbut configuring the reflectors differently such that two or morereflector configurations are employed. It is contemplated that eachreflector could be of a different configuration to reach the desiredlight distribution.

With reference to FIG. 10, another embodiment of a portion of a lightingapparatus 10 is shown and described. The lighting apparatus 10 includesa base member 110 having a first surface 114 having a plurality ofreflective elements 70 extending from the base member 110. A pluralityof openings 118 are also shown in the base member 110. The openings 118are arranged in a pattern, such a matrix of rows and columns similar toa checkerboard or some other pattern. Each of the openings 118 isconfigured to receive a respective light source 52 (e.g., a LED). Inother embodiments, the base member has a different shape, for example,substantially circular. That is the base member 110 and the directionalmembers, which are described below, form a wheel-and-spoke type pattern.Also, in other embodiments, the base member 110 and the directionalmembers form a “fan” type configuration.

The lighting apparatus also includes one or more directional members122. Each directional member 122 has a portion of a reflective surface(not shown) positioned relative to at least one opening 118 of the basemember 110 to reflect light radiating from the lighting source 52disposed within the opening 118. The reflection is generally directedtowards a portion of at least one of the reflective elements 70extending from the base member 110.

The lighting apparatus 10 also includes, in various embodiments, a pairof side members 126 that are attached to or formed integral with thebase member 110. Each of the side members 126 has a reflective face.When the side members 126 are attached to the base member 110, thereflective faces typically face one another.

In more detail and with reference to FIG. 11A, FIG. 11B, FIG. 11C, andFIG. 11D further details of the embodiment of a portion of the lightingapparatus of FIG. 10. As shown in the side view of FIG. 11B, thedirectional member 122 extends through one or more of the reflectiveelements 70. In one embodiment, a portion of the reflective elements 70is removed to create a cut-out 130 having shape that compliments that ofa portion of the directional member 122. In one embodiment, thedirectional member 122 has a v-shaped cross section and the cut-out 130is shaped to receive the directional member 122, as shown in FIG. 11C.In other embodiments, the directional member 122 has another shape. Forexample, the directional member can be a single piece of reflectivematerial positioned at a specific angle relative to the base member 110.Said another, the reflective member can be, in some embodiments, oneside of the v-shaped directional member 122. In other embodiments, thereflective member 122 has a u-shaped, a parabolic, or other shape crosssection.

In one embodiment, the cut-out 130 supports the directional member 122when inserted through the cut-out 130. The depth, as measured from thefirst surface 114 of the base member 110 controls the amount of materialthat is present to support the directional member 122. In anotherembodiment, the directional member 122 is attached to opposing ends ofthe base member 110. As seen from the top view of FIG. 11A, whenlighting sources 52 are not disposed in the openings 118, a portion ofthe reflective member 122 can be seen through the opening 118. When thelighting source 52 is present, the light radiating from the lightingsource 52 is directed, at least in part, towards the reflectors 70and/or reflective members 122, which, in turn, reflect the radiatedlight according to a desired pattern.

As shown, the cross-section of the reflective elements 70 is v-shaped.Further, as shown in FIG. 11B the v-shaped cross-section for thereflector can also be used in an embodiment that, in some instances,lacks the directional member 122. Other shaped cross-sections can beused as well. For example, a substantially u-shaped, parabolic, or othercross section can be employed. Also, as shown in FIG. 11D the basemember 110 and reflective members 70 can be formed integrally from asingle contiguous piece of material (e.g., sheet metal).

With reference to FIG. 12A and FIG. 12B, an exemplary embodiment of thebase member 110 that is formed to create reflective elements 70. Thespecific lengths and angles of each portion of the base member 110 areprovided as mere examples and are not intended to be limiting thedisclosure to a single embodiment. As shown in FIG. 12B, the base member110 has a first surface 114 that is reflective in nature (e.g., polishedsheet metal). Also include in the base member are the openings 118 andthe cut-outs 130. Also, shown are tabs 134 that can be used to securethe base member 110 to the side member 126 using a corresponding slot138 (see FIG. 13). As shown, the base member 110 is bent at specifiedangles and specified locations to create a portion of the lightingapparatus 10.

With reference to FIG. 13, a top view of side member 126 is shown. Inone embodiment, the side member has one or more slots 138 configured toreceive a corresponding tab 134 of the base member 110. The tab 134 canbe inserted and bent to attach the side member 126 to the base member110. The dimensions shown in FIG. 13 are only exemplary and not intendedto limit the disclosure. As stated above, at least one of the faces ofthe side member 126 is reflective.

While the disclosure makes reference to the details of preferredembodiments of the disclosure, it is to be understood that thedisclosure is intended in an illustrative rather than in a limitingsense, as it is contemplated that modifications will readily occur tothose skilled in the art, within the spirit of the disclosure and thescope of the appended claims.

We claim:
 1. A luminaire comprising: a plurality of lighting sources; acoverplate comprising: a base defining a plurality of openings, one ormore of the plurality of openings receiving a lighting source; aplurality of reflectors extending from the base, at least one of theplurality of reflectors extending adjacent at least one of the pluralityof openings, at least one of the plurality of reflectors having a firstside and a second side defining a distal edge of the reflector; and atleast one side portion extending generally outward from the base andtapered outwardly.
 2. The luminaire of claim 1, wherein a plurality ofthe lighting sources are arranged in a first row oriented in a firstdirection, a plurality of the lighting sources are arranged in a secondrow oriented in the first direction, and at least one of the pluralityof reflectors extends from the base member between the first row oflighting sources and the second row of lighting sources and is orientedin the first direction.
 3. The luminaire of claim 1, wherein the atleast one side portion comprises two sides portions.
 4. The luminaire ofclaim 1, wherein the coverplate further comprises end portions extendinggenerally outward from the base.
 5. The luminaire of claim 1, wherein atleast one of the plurality of reflectors extends from the base member atan angle δ of about 0° to about −20° from perpendicular to the base. 6.The luminaire of claim 1, wherein the luminaire is a roadway luminaire.7. The luminaire of claim 1, wherein the first side and second side ofat least one of the reflectors form a substantially V-shapedcross-section.
 8. The luminaire of claim 1, at least one of theplurality of lighting sources is an LED.
 9. The luminaire of claim 8, anoptic associated with the LED.
 10. A luminaire comprising: a housingdefining a cavity; a plurality of lighting sources; a coverplatecomprising: abase defining a plurality of openings, one or more of theplurality of openings receiving a lighting source; a plurality ofreflectors extending from the base, at least one of the plurality ofreflectors extending adjacent at least one of the plurality of openings,at least one of the plurality of reflectors having a first side and asecond side defining a distal edge of the reflector; and at least oneside portion extending generally outward from the base and taperedoutwardly toward the housing.
 11. The luminaire of claim 10, wherein aplurality of the lighting sources are arranged in a first row orientedin a first direction, a plurality of the lighting sources are arrangedin a second row oriented in the first direction, and at least one of theplurality of reflectors extends from the base member between the firstrow of lighting sources and the second row of lighting sources and isoriented in the first direction.
 12. The luminaire of claim 10, whereinthe at least one side portion comprises two sides portions.
 13. Theluminaire of claim 10, wherein the coverplate further comprises endportions extending generally outward from the base and tapered outwardlytoward the housing.
 14. The luminaire of claim 10, wherein at least oneof the plurality of reflectors extends from the base member at an angleδ of about 0° to about −20° from perpendicular to the base.
 15. Theluminaire of claim 10, wherein the luminaire is a roadway luminaire. 16.The luminaire of claim 10, wherein the first side and second side of atleast one of the reflectors form a substantially V-shaped cross-section.17. The luminaire of claim 10, at least one of the plurality of lightingsources is an LED.
 18. The luminaire of claim 17, an optic associatedwith the LED.
 19. A luminaire comprising: a housing having sidewalls,each defining a distal edge, and the sidewalls collectively defining acavity; a plurality of lighting sources; a coverplate comprising: a basedefining a plurality of openings, one or more of the plurality ofopenings receiving a lighting source; a plurality of reflectorsextending from the base, at least one of the plurality of reflectorsextending adjacent at least one of the plurality of openings, at leastone of the plurality of reflectors having a first side and a second sidedefining a distal edge of the reflector; and at least one side portionextending generally outward from the base and tapered outwardly towardthe distal edge of an associated housing sidewall.
 20. The luminaire ofclaim 19, wherein a plurality of the lighting sources are arranged in afirst row oriented in a first direction, a plurality of the lightingsources are arranged in a second row oriented in the first direction,and at least one of the plurality of reflectors extends from the basemember between the first row of lighting sources and the second row oflighting sources and is oriented in the first direction.
 21. Theluminaire of claim 19, wherein the at least one side portion comprisestwo sides portions.
 22. The luminaire of claim 19, wherein thecoverplate further comprises end portions extending generally outwardfrom the base and tapered outwardly toward the distal edge of associatedhousing sidewalls.
 23. The luminaire of claim 19, wherein at least oneof the plurality of reflectors extends from the base member at an angleδ of about 0° to about −20° from perpendicular to the base.
 24. Theluminaire of claim 19, wherein the luminaire is a roadway luminaire. 25.The luminaire of claim 19, wherein the first side and second side of atleast one of the reflectors form a substantially V-shaped cross-section.26. The luminaire of claim 19, at least one of the plurality of lightingsources is an LED.
 27. The luminaire of claim 26, an optic associatedwith the LED.
 28. A luminaire comprising: a plurality of lightingsources arranged in a substantially matrix-like pattern comprising afirst row of lighting sources, a second row of lighting sources and athird row of lighting sources; a coverplate of sheet material comprisinga substantially planar base defining a plurality of openings comprisinga first row of openings, a second row of openings and a third row ofopenings, one or more of the first row of lighting sources disposed inone or more of the first row of openings, one or more of the second rowof lighting sources disposed in one or more of the second row ofopenings, one or more of the third row of lighting sources disposed inone or more of the third row of openings; and a reflector extendingintegrally from the coverplate between the first row of openings and thesecond row of openings, the reflector having a reflective surface facingan adjacent one of the second row of openings and oriented at an angle δof about 0° to about −20° from perpendicular to the substantially planarbase.
 29. The luminaire of claim 28, the reflector comprising anelongated reflector extending the entire length of the first row ofopenings.
 30. The luminaire of claim 28, the reflector comprising anelongated reflector extending the entire length of the first row oflighting sources.
 31. The luminaire of claim 28, the coverplate furthercomprising at least one side portion extending generally outward fromthe base.
 32. The luminaire of claim 28, wherein the coverplate furthercomprises end portions extending generally outward from the base. 33.The luminaire of claim 28, the coverplate further comprising a secondreflector extending integrally from the coverplate between the secondrow of openings and the third row of openings, the second reflectorhaving a reflective surface facing an adjacent one of the third row ofopenings and oriented at an angle δ of about 0° to about −20° fromperpendicular to the substantially planar base.
 34. The luminaire ofclaim 28, wherein the luminaire is a roadway luminaire.
 35. Theluminaire of claim 28, wherein the reflector comprises a first side anda second side forming a substantially V-shaped cross-section.
 36. Theluminaire of claim 28, at least one of the plurality of lighting sourcesis an LED.
 37. The luminaire of claim 36, an optic associated with theLED.